Recycle graphite from spent lithium-ion batteries for H₂O₂ electrosynthesis

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Science

Background:

• On-site hydrogen peroxide (H₂O₂) synthesis via oxygen reduction reaction is crucial for environmental remediation.
• Spent graphite from lithium-ion batteries presents a disposal challenge and an opportunity for resource recovery.

Purpose of the Study:

• To develop a sustainable and cost-efficient method for preparing H₂O₂ electrosynthesis catalysts from spent graphite.
• To investigate the efficacy of recycled graphite as a catalyst for H₂O₂ generation and wastewater treatment.

Main Methods:

• Recycling spent graphite from lithium-ion batteries.
• Activating graphite using nitric acid (HNO₃) to introduce carboxyl (-COOH) and ether (C-O-C) functional groups.
• Electrochemical synthesis of H₂O₂ using the activated graphite catalyst.

Main Results:

• The activated graphite catalyst achieved a high H₂O₂ Faradaic efficiency of approximately 80%.
• The catalyst demonstrated significant activity and selectivity for H₂O₂ production compared to raw spent graphite.
• Application in treating T-acid wastewater resulted in the removal of nearly 92% of chemical oxygen demand.

Conclusions:

• Spent graphite can be effectively recycled into an eco-friendly and cost-efficient catalyst for H₂O₂ electrosynthesis.
• The activated graphite catalyst shows great potential for environmental remediation, particularly in treating industrial wastewater.